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Blueberries have high nutritional and economic value and are easy to cultivate, so they are common fruit crops in China. There is a high demand for blueberry in domestic and foreign markets, and various technologies have been used to extend the supply cycle of blueberry to about 7 months. However, blueberry grows in clusters, and a cluster of fruits generally contains fruits of different degrees of maturity, which leads to low efficiency in manually picking mature fruits, and at the same time wastes a lot of manpower and material resources. Therefore, in order to improve picking efficiency, it is necessary to adopt an automated harvesting mode. However, an accurate maturity detection model can provide a prerequisite for automated harvesting technology. Therefore, this paper proposes a blueberry ripeness detection model based on enhanced detail feature and content-aware reassembly. First of all, this paper designs an EDFM (Enhanced Detail Feature Module) that improves the ability of detail feature extraction so that the model focuses on important features such as blueberry color and texture, which improves the model's ability to extract blueberry features. Second, by adding the RFB (Receptive Field Block) module to the model, the lack of the model in terms of receptive field can be improved, and the calculation amount of the model can be reduced at the same time. Then, by using the Space-to-depth operation to redesign the MP (MaxPool) module, a new MP-S (MaxPool–Space to depth) module is obtained, which can effectively learn more feature information. Finally, an efficient upsampling method, the CARAFE (Content-Aware Reassembly of Features) module, is used, which can aggregate contextual information within a larger receptive field to improve the detection performance of the model. In order to verify the effectiveness of the method proposed in this paper, experiments were carried out on the self-made dataset "Blueberry—Five Datasets" which consists of data on five different maturity levels of blueberry with a total of 10,000 images. Experimental results show that the mAP (mean average precision) of the proposed network reaches 80.7%, which is 3.2% higher than that of the original network, and has better performance than other existing target detection network models. The proposed model can meet the needs of automatic blueberry picking. [ABSTRACT FROM AUTHOR]

This research paper explores the development of selective harvesting technology for cauliflower, aiming to improve efficiency and reduce labor-intensive manual harvesting methods. The study focuses on determining the design parameters for an efficient selective cauliflower harvester based on the physical and mechanical properties of cauliflower plants. Various physical properties of the plants, such as width, height, curd diameter, and stalk moisture content, were measured to provide valuable insights for the advancement of agricultural robotics and engineering. The research aims to contribute to the development of advanced selective harvesting technologies and enhance overall crop productivity. [Extracted from the article]

Copyright of INMATEH - Agricultural Engineering is the property of INMATEH - Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of INMATEH - Agricultural Engineering is the property of INMATEH - Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Approximately one-third of the global food supply is lost or wasted each year. Given that the harvesting process is the initial stage following food production, minimizing losses in this crucial phase holds paramount significance in augmenting the food supply and ensuring food security. The 1959–1961 famine in China was one of the most catastrophic events in history and had long-term effects on human beings, particularly farmers. This paper aims to provide a new perspective on the variations in harvest losses across age cohorts by examining the impact of famine experiences. Using survey data from the 2016 Postproduction Food Loss and Waste Survey conducted by China Agricultural University and the Rural Economic Research Center, which involved 3538 farming households across 28 provinces, we construct a cohort difference-in-difference (DID) model to investigate the impact of famine experience on household harvest losses. The standard cohort DID estimation results indicate that in areas with severe famine, a 1% increase in excess mortality would reduce the rate of harvest loss by 3%, suggesting that farmers who have experienced extreme famine have a deeper memory of the event, which subsequently helps them reduce harvest losses. Moreover, the results of the heterogeneity test reveal that the more serious the famine that the household head experienced in early life was, the less harvest losses there were, particularly for those who were adolescents during the famine. The findings elucidate the importance of historical events in shaping current behaviors and contribute to a better understanding of the variation in harvest losses across age cohorts. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Applied Chemistry is the property of Chinese Journal of Applied Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Currently, Epimedium Sagittatum is the mainstream Epimedium present in the market of China. It has the functions of tonifying kidney Yang, strengthening muscles and bones, and removing wind and dampness. It is mainly used in clinical practice to tonify kidney and strengthen Yang, which is one of the most potential and key Chinese medicines. At present, the lack of unified standards for cultivation, harvesting and processing of Epimedium has resulted in a wide variety of quality differences in the market. Based on literature review, this paper reviews the quality status of Epimedium, and summarizes the influences on quality control of Epimedium from six aspects, including variety, place of origin, cultivation, harvest time, harvest site and processing method. In order to improve the overall quality of Epimedium, it is suggested that systematic research should be conducted on planting, harvesting, processing and storage of Epimedium, and unified cultivation technical regulations should be formulated to meet the good agricultural practice in planting specifications. [ABSTRACT FROM AUTHOR]

Copyright of INMATEH - Agricultural Engineering is the property of INMATEH - Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As agricultural labor is decreasing, famous tea production is nearly hard to sustain and is getting more and more expensive in China. To improve the mechanization of tea plucking, this paper designs a self-propelled track-type tea plucking machine that integrates mechanic, hydraulic and electronics. The main parameters of chassis were optimized based on conditions of tea garden. And, three different kinds of cutter blades were designed and analyzed about vibration performance with finite element software. Also, a rigid-flex mixed motion model was established. Based on the model and plots, it is explicit that: 1) the blades move in a sine law; 2) the blades take a symmetrical deform from middle to end while moving; 3) the deformation increases along the blade from the center to sides. The single factor experiment revealed that both travel speed and speed ratio of cutting and travelling had a significant effect on quality indexes (integrity rate, unpicking rate, stubble unevenness) of plucked tea leaf. By universal rotary combination experiment of quadratic regression, the regression equations of three indexes about two experimental factors were established. And, the comprehensive optimization of three indexes was conducted with software Design expert. The optimal operating parameters of machine are as follow: travel speed is 0.41 m/s, speed ratio of cutting and travelling is 1.06; prediction of three indexes are that integrity rate could be reach to 78.26%, unpicking rate reduced to 0.82%, stubble unevenness reduced to 1.30 mm. The results of verification experiment are that: integrity rate could be reach to 77.41%, unpicking rate reduced to 0.87%, stubble unevenness reduced to 1.23 mm. These test indexes that are very close to the predicted values, all surpass the requests specified in the standard of tea plucking with machine. In all, the optimized parameter set is indeed synthetically optimal one that enables the wide use of this tea plucking machine, which can be used in the tea garden that has a lengthways slope less than 18°, a crosswise slope less than 20°, and a height of tea trees between 50-120 cm. From above, the tea plucking machine investigated in this paper provides an effective solution to present tea picking problem that is the bottleneck of tea industry. Further studies need to do for making this machine more automated and intelligent. [ABSTRACT FROM AUTHOR]

Purpose -- The purpose of this paper is to analyze the efficiency of temperature-based weather derivatives (WD) in reducing risk exposure for Chinese agriculture industry. Therefore, a put option with cumulated growing degree days as its underlying index is assumed to be bought by farmers as a risk management instrument to prevent income fluctuations from adverse temperature conditions. Design/methodology/approach -- The objective of this paper is to analyze the efficiency of temperature-based WD in reducing risk exposure for Chinese agriculture industry. Therefore, a put option with cumulated growing degree days as its underlying index is assumed to be bought by farmers as a risk management instrument to prevent income fluctuations from adverse temperature conditions. Findings -- The results of the efficiency tests show that temperature-based put options are efficient in offsetting yield shortfalls for rice and wheat in China. The weather-yield models have a high prediction power in explaining yield variation by temperature. Research limitations/implications -- The de-trending procedure for the weather-yield model should be improved to distinguish better between technology progress, human activities and influence of weather. Further, more advanced models could be used for the pricing. Practical implications -- The findings of the paper support the launch of WD as an efficient risk management tool for agriculture in China. Compared with traditional damage-based insurance, WD are more flexible, have lower transactions costs and avoid moral hazard or adverse selection. Originality/value -- The efficiency problem of WD has not been analyzed sufficiently worldwide and especially not for developing countries like China where a large proportion of the population works as farmers. This paper supports to fill this gap. [ABSTRACT FROM AUTHOR]

This paper outlines a model for the domestication of Panicum miliaceum (broomcorn millet) in Northern China. Data from 43 archaeological sites indicate a continuous increase in average grain size between 6000 and 3300 bc. After this date there is a divergence, with grain size continuing to increase in some populations, while others show no further size increase. The initial increase in grain size is attributed to selection during domestication, while later divergence after 3300 bc is interpreted as resulting from post-domestication selection. Measurements of grains from two archaeological populations of P. ruderale, showed grains were longer in length by 3300 bc than the earliest grains of P. miliaceum. This suggests this sub-species includes many feral, weedy and/or introgressed forms of P. miliaceum and therefore is probably not entirely representative of the true wild ancestor. It is argued that changes from shattering to non-shattering are contemporary with increasing grain size and the commencement of cultivation. The window of P. miliaceum domestication is therefore likely to lie between 7000 and 3300 bc. However, it is probable that a lengthy period of millet harvesting and small-scale management preceded its domestication. [ABSTRACT FROM AUTHOR]

Understanding the contribution of aboveground dry matter (DM) production and harvest index (HI) to maize grain yield is essential to further improve grain yield to ensure future food growing requirements. In this study, we collected 548 sets of data of DM, HI, and grain yield from a multisite (40 sites) and multiyear (2009–2016) experiment conducted in major maize‐growing regions across China and 615 sets of data from 40 published papers distributed from 1988 to 2018 to assess the performance of DM, HI, and their contributions to grain yield. It was found that the average contribution rate of DM was 73.71%, which was much higher than those of HI (26.28%) across China. For the five different modern hybrids, the contribution rates of DM to grain yield (ranged from 71.36% to 89.10%) were also significantly higher than those of HI (ranged from 10.79% to 28.64%) on a large spatial scale. The significant differences in grain yields between cultivars were mainly due to the differences in HI. Among the four maize‐growing regions, the contribution rates of DM in both NW (57.34%) and NM (64.46%) were higher than those of HI (42.66% and 35.54%, respectively). In contrast, the contribution rates of HI in HM (52.67%) and SW (50.92%) were slightly higher than those of DM (47.33% and 49.08%, respectively). The interregional differences in grain yield were mainly attributed to the differences in DM between regions. Additionally, combining the data of this study and data collected from previous studies, we found that the increase in maize grain yield under lower yield levels (<15 Mg/ha) was mainly attributed to the increase in both DM and HI, while that under higher yield levels (>15 Mg/ha) was mainly dependent on the increase in DM. [ABSTRACT FROM AUTHOR]

Corydalis saxicola is a perennial herbaceous plant, which mainly distributed in the karst areas of southwest China. Due to its important ecological and medicinal value, Corydalis saxicola has great prospects for development and utilization. With fragile living environmental condition and anthropogenic harvesting pressure, the wild resource of Corydalis saxicola is on the verge of exhaustion, so it has been included in the list of national key protected wild plants in 2021. In order to explore the causes for the endangerment of Corydalis saxicola and provide reference for its conservation and seedling breeding, this paper investigated the influencing factors on seed germination that including seed preservation methods, chemical pre-treatments, temperature, light, drought, pH, mix with wet sand and refrigerate treatment. The results were as follows:(1)Low-temperature storage can prolonged the seed activity, germination rate of 2-years stored seed could still reached 30%.(2)Germination rates of seed pre-treatments by HCl and NaClO solutions can reached to 50%～60%; germination rate was 50% at 20 ℃, while closed to zero at 30 ℃; darkness was more favorable for seed germination than periodic light condition; the seed germination rate kept decreasing with deepening drought; the seed germination rate did not changed significantly under the conditions of pH 3.0～8.0.(3)Mix with wet sand and refrigerate treatment can significantly promoted the seed germination potential and germination rate, and the germination rate was twofold of the control. In summary, the seed inactivation at room temperature and germination inability at high temperatures above 30 ℃ are more related to its endangerment; efficient seed germination methods can provide an effective way for conservation and industrial application of Corydalis saxicola. The results provide a theoretical and technical guarantee for the conservation of wild Corydalis saxicola, and technically support is cultivation. [ABSTRACT FROM AUTHOR]

This paper proposed a technical idea of joint operation of conveying and grading and developed a potato conveying and grading device with variable space to realize efficient grading in the field because of the difficulties of field grading in the process of potato harvesting in the hilly mountains of northwest China. Based on field measurement of potato size distribution, the clearance between rotating plates of potato conveying and grading device was determined. The key structural parameters of the rotating plate were obtained by referring to the structure and relevant parameters of the conveying and grading device. Moreover, the conveyor chain elevation angle of the conveying and grading device was determined through the dynamics analysis of potatoes on the conveying and grading device. The inclined plane test determined the inclination angle of the potato guide plate. To reduce the damage to potatoes in the process of conveying and grading, damage analysis was carried out. Finally, Field tests were conducted with conveyor chain elevation angle, unit forward speed, and the conveyor chain line speed as test factors, and the grading accuracy and the damage rate of the potato conveying and grading device as test indexes. The test results showed that when the conveyor chain elevation angle, unit forward speed, and conveyor chain line speed were 21.0°, 0.8 m/s, and 1.3 m/s, respectively, the grading accuracy was 91.4% and the rate of potato damage was 0.88%. The operational performance of the prototype was stable, and all the test evaluation indicators could meet the agronomic requirements of the potato harvester. [ABSTRACT FROM AUTHOR]

In China, historical documents record a large quantity of information related to climate change and grain harvest. This information can help to explore the impacts of extreme drought or flood on crop production, which can provide implications for the adaptation of agriculture to higher-probability extreme climate in the context of global warming. In this paper, reported extreme drought/flood chronologies and reconstructed grain harvest series derived from historical documents were adopted in order to investigate the association between the reported frequency of extreme drought/flood in eastern China and reconstructed poor harvests during 801–1910. The results show that extreme droughts were reported more often in 801–870, 1031–1230, 1481–1530, and 1581–1650 over the whole of eastern China. On a regional scale, extreme droughts were reported more often in 1031–1100, 1441–1490, 1601–1650, and 1831–1880 in the North China Plain, 801–870, 1031–1120, 1161–1220, and 1471–1530 in Jianghuai, and 991–1040, 1091–1150, 1171–1230, 1411–1470, and 1481–1530 in Jiangnan. The grain harvest was reconstructed to be generally poor in 801–940, 1251–1650, and 1841–1910, but the reconstructed harvests were bumper in 951–1250 and 1651–1840, approximately. During the entire period from 801 to 1910, the frequency of reporting of extreme droughts in any subregion of eastern China was significantly associated over the long term with lower reconstructed harvests. The association between reported frequency of extreme floods and reconstructed low harvests appeared to be much weaker, while reconstructed harvest was much worse when extreme drought and extreme flood in different subregions were reported in the same year. The association between reconstructed poor harvests and reported frequency of regional extreme droughts was weak during the warm epoch of 920–1300 but strong during the cold epoch of 1310–1880, which could imply that a warm climate could weaken the impact of extreme drought on poor harvests; yet other historical factors may also contribute to these different patterns extracted from the two datasets. [ABSTRACT FROM AUTHOR]

Moisture content is one of the important indicators in grain harvesting, trading, storage and processing. High moisture content will lead to a series of problems of grain such as mildew, deterioration, shortened storage time, lower transaction price and higher processing cost. With the development of precision agriculture, accurate detection of grain moisture content can also accurately assess the growing situation of crops, and then provide guidance for the next season’s crop planting. Compared with the drying method, the capacitance method and the electric resistance method, the microwave method is easy to realize the non-destructive measurement of the grain moisture content, which is an important direction of moisture content detection. In the field of on-line detection of moisture content of rice and wheat in combine harvesters, foreign related research started earlier, and enterprises have commercialized, but this technology is still in the research stage in China. Aiming at the problem that the rice-wheat combine harvester is difficult to accurately measure the moisture content of wheat and rice during harvesting operation, this paper studied a non-destructive on-line detection method of grain moisture content based on microwave reflection method, established the grain moisture content measurement model, designed a non-destructive on-line detection device for grain moisture content used on rice-wheat combine harvesters. The device used a 450 MHz microwave measurement module to measure the moisture content of rice and wheat non-destructively. The voltage conversion circuit was designed to convert microwave parameters into voltage signals, and the average filtering algorithm was used for signal filtering to reduce the impact of interference factors. Finally, the moisture content detection model of rice and wheat, which was established by the calibration experiment, was used to calculate the moisture content. The calculation result was displayed on the display in real time via CAN bus communication. Due to the insufficient installation space in rice-wheat combine harvester, the structure of the detecting device was designed and optimized, and the circuit portion and the sampling mechanism were integrated in a compact structure. Based on the above theoretical research, technology development and structural design, this paper carried out laboratory static experiments and field harvesting experiments. The laboratory static experiment used rice and wheat to illustrate the establishment process of the grain moisture content detection model: 30 groups of rice and 30 groups of wheat samples were prepared, moisture contents and voltages calibration experiment was completed, the rice and wheat moisture content detection models was established and the experimental results were analyzed. The field harvesting experiment was verified the practicability and reliability of the grain moisture content detecting device with rice as the test object. The experiment results show that the performance standard deviations of the laboratory static experiment and the field harvest experiment are 0.458 3 and 1.078 0, respectively, and the relative error are around 2.5% and 5%, respectively. Moisture content measuring range of the detection device for rice and wheat is 14%-34%, which meets the project requirements. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

How much of China’s recent economic performance can be attributed to market-oriented reforms introduced in the last two decades? A long-run perspective may be important for understanding the process of economic development occurring today. This paper compares the integration of rice markets in China today and 270 years ago. In the eighteenth century, transport technology was non-mechanized, but markets were close to being free. We distinguish local harvest and weather from aggregate sources of price variation in a historical sample and in a similarly constructed contemporary sample. Findings indicate the degree of market integration in the 1720s is a very good predictor of per capita income in the 1990s. Moreover, the current pattern of interregional income in China is strongly linked to persistent geographic factors that were already apparent several centuries ago, well before the enactment of modern reform programs. [ABSTRACT FROM AUTHOR]

Purpose In China, a major grain producer, rice losses during harvest cannot be ignored. The purpose of this paper is to assess the extent of rice harvest losses in major grain-producing areas in China by a sampling survey, and to further analyze the main factors influencing rice harvest losses using an ordered multinomial logistic model.Design/methodology/approach In this study, data were collected using a multi-stage sampling method from ten major rice-producing provinces/regions in China. On this basis, five counties were selected from each of these provinces/regions. In the actual survey, house numbers were randomly selected, and then corresponding farmer households were visited by trained investigators.Findings The survey found that 56.22 percent of respondents believed that rice harvest losses were 4 percent or lower in China, though there were differences among the provinces. The proportion of family business income, planting scale, mechanization level, timely harvest, and operational meticulousness had negative effects on rice harvest losses. On the other hand, farmers’ experience of employment as migrant workers had a positive effect on rice harvest losses. In addition, bad weather and short handedness during harvest significantly increased rice harvest losses.Originality/value The meaning of rice harvest losses was defined based on previous research findings on the definition of grain harvest losses and the realities in China. The current rice harvest losses in different areas in China were analyzed based on sampling survey data from 957 farmers in ten provinces in China. [ABSTRACT FROM AUTHOR]

Caragana korshinskii Kom. (CKK) is one of the main trees for wind and sand control in northwest China. According to its biological characteristics, flat stubble is the main measure and the critical stage of nurturing management. However, the quality of the CKK sawing surface not only affects the sprouting rate of the following year but also reflects the mechanical properties of flat stubble. To reduce the sawing power consumption of the CKK stubble device and improve the quality of sawing cross-section, this paper conducted branch sawing tests on a self-designed sawing experiment rig. Using the central composite design test method, the operating parameters of the sawing experiment rig were studied experimentally, with sawing speed (v a), moving speed (v ' f), and inclination angle of the circular blade (α) as the influencing factors, sawing power consumption (Y 1) and cross-section integrity rate (Y 2) as the objective functions, to establish a multiple mathematical regression model between them. The test results show that the influence of each factor on the sawing power consumption in the order of significance is the v a , v ' f , and α, and the influence of each factor on the cross-section integrity rate in the order of significance is the v ' f , v a , and α. The optimal combination of working parameters is v a of 42 m/s, v' f of 0.3 m/s, and α of 10°, which corresponds to Y 1 and Y 2 of 279.73 W and 82.6% respectively. Based on the optimal combination of working parameters, the prototype was processed and field tests were conducted. The field test results showed that the stubble breaking rate and missed cutting rate of the CKK harvester are 5.5% and 4.7% respectively, and the CKK branches sprouted well in the following year after flattening the stubble, which all met the requirements of the CKK harvesting operation. • For the unique growth mode of CKK, the sawing method was chosen through actual investigation in the field. • For CCK harvesters, cross-section integrity directly determines the sprouting rate of the following year. • The central combination test method was used to explore the effects of the test factors on the target values. • It was verified through field trials that the circular saw operated well with an optimized combination of cutting parameters. [ABSTRACT FROM AUTHOR]

Zizania latifolia (Z. latifolia) is a popular aquatic vegetable with various nutrients in south China, but little is known about its cultivars and growing seasons in terms of the nutritional components. This work aims to characterize the nutrients of five Z. latifolia cultivars in different growing seasons. The results showed that Z. latifolia samples differed in terms of chemical parameters, which were significantly affected by variety, growing season, and their interaction. Zhejiao No. 8, harvested in the autumn, stood out with the highest levels of vitamin C. Tangxiajiao and Zhejiao No. 1 contained the highest values of total soluble solids, reducing sugar, soluble proteins, and amino acids. Significant differences were observed between the autumn Z. latifolia and spring samples; the former were of higher quality than the latter based on hierarchical clustering analysis and principal component analysis. Moreover, total amino acids (TAA) and glutamic acid (GLU) were selected as the key indicators for Z. latifolia comprehensive quality by multiple linear regression analysis. This study provides essential information on Z. latifolia quality characteristics corresponding to cultivars and growing seasons, which lays the foundation for promoting the quality improvement of Z. latifolia scientifically. [ABSTRACT FROM AUTHOR]

The high harvest losses associated with the mechanical harvesting of maize in China are currently a major barrier to the adoption of this technology. This paper summarizes works of literature regarding harvest losses from the combine harvesting of maize in China and abroad. The main findings are as follows: (1) In 2012-2019, 2987 samples data obtained from the major maize production areas of China showed that the average harvest loss was 345.2 kg/hm² (3.5% of the average yield), with losses ranging from 0 to 9288.5 kg/hm²; (2) The harvest losses from combine harvesting are mainly caused by the dropping of ears. The ear losses include the pre-harvest loss caused by ear abscission, damage caused by maize borer, lodging, and the ear loss during combine harvesting, and the main pre-harvest loss is caused by lodging; (3) Harvest losses are affected by maize variety, planting mode, cultivation management, pests and diseases, weather conditions during harvesting, harvest date, combine harvester type, harvester adjustment, operator proficiency, and the terrain conditions of the maize field; (4) The harvest losses from combine harvesting are also related to the type of header, feeding and threshing methods, the adjustment of header stripping clearance, feeding amount, forward speed, cylinder or rotor speed, and the clearance between the cylinder and the concave of the harvester. However, the combine losses mainly come from header losses. In order to reduce the harvest losses, the following solutions were proposed: (1) Breed and select maize varieties which are resistant to lodging, especially during the field drying of mature grains, as well as those resistant to maize borer and stalk rot; (2) Select varieties suitable for grain harvest--which requires matching the accumulated-temperature demand of the maize hybrids, optimal plant density, row spacing, and irrigation and fertilizer management with the light and heat conditions of the production area while cultivating uniform populations and healthy plants--as well as preventing and controlling damage from maize borer, stalk rot, and ear rot, harvesting at the appropriate time; (3) Develop and select advanced maize combine harvesters, formulate standardized operating procedures for harvesting machinery, and standardize field operation; (4) select appropriate agricultural machinery and agronomic practices, and improve the training of maize producers and harvester operato [ABSTRACT FROM AUTHOR]

Burning is one of the most widely used methods for removing crop residues during harvest seasons. It cleans fields faster and costs less in comparison to other residue removal methods. Agricultural burning, however, has been recently limited or banned during harvest seasons in China, mainly due to the air quality and human health concerns raised from its use. This paper reviews recent studies on the burning of agricultural landscapes in China to understand the natural (environmental and ecological) and human (economic and social) impacts and identifies uncertainties, gaps, and future research needs. The total annual crop straw output in China is more than 600 billon kg, with about 110, 130, and 230 billion kg coming from rice, wheat, and corn, respectively. Agricultural burning removes about one-fourth of total crop straw and emits about 140-240, 1.6-2.2, and 0.5-0.14 billion kg of CO, PM, and black carbon, respectively. Agricultural burning accounts for upto half of the total PM concentrations in the major burning regions during harvesting periods. Burning emissions contribute to regional haze and smog events. Therefore, limiting or banning agricultural burning is a necessary measure for reducing air pollution in China. The estimations of total burned crop straw amounts and emission factors are the major uncertainty sources for emission estimates. More studies are needed to better describe the smoke plume rise, dispersion, and interactions with weather and climate and to simulate the ecological impacts of agricultural burning. Effective alternatives need to be explored in order to provide solutions for farmers to remove agricultural residues in the wake of the burning ban. [ABSTRACT FROM AUTHOR]

Copyright of Journal of World Prehistory is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】In order to provide technical support for mechanized production of early maturing rape in Southwest China,the new varieties and planting density suitable for early maturing and mechanized harvesting were selected.【Method】Through the analysis and comparison of the growth period and multiple harvest related indexes of 15 rape varieties bred by 5 units in Southwest China in recent years,the paper evaluated the early maturing and the key indexes of suitable for mechanized harvest,and analyzed the correlation analysis of yield,related characters and multiple indexes of suitable for mechanized harvest under different planting density for obtaining suitable planting density.【Result】 The results showed that more than 73 % of the varieties had outstanding precocity,and 53 % had good consistency of concentrated maturity,and 30 % had good suitable harvest indexes.Three varieties,Yunyouza No.12,Yuyou 55,Yizaoyou No.1,had the outstanding characteristics of early maturity and suitable for mechanized harvesting.With the increase of planting density,the yield of the varieties increased first and then decreased.Selecting compact plant type varieties and increasing density properly could reduce plant height and weight per plant,reduce lodging and increase yield.There was a positive correlation between the crack resistance index and the number of grains per corner and 1000 grain weight,especially the correlation coefficient with 1000 grain weight was more than 0.49.【Conclusion】In this experiment,three new early maturing rape varieties suitable for mechanical harvest were selected,and all of them showed the highest yield under the condition of 200 000 plants/hm2. [ABSTRACT FROM AUTHOR]

In view of the problems existed of sugarcane harvester in China, the paper analyzes the types and characteristics of the existing sugarcane collection mechanism. A new type of three degree of freedom sugarcane harvester hybrid drive collection mechanism was designed in three dimensions. The geometric model of the new configuration related components and the overall assembly was established. And imported into the ADAMS simulation software. After the simulation, the working point and the force curve of the component node were output and analyzed. In order to obtain the motion law of the new three-degree-of-freedom stacking mechanism, verify the correctness of the theoretical model, and provide reference for the in-depth research and prototype trial production of the stacking mechanism in the future. [ABSTRACT FROM AUTHOR]

The stem tip of vegetable sweet potato is an excellent nutritious and healthy food, which is widely used in many countries. It’s estimated that the total value of Chinese vegetable sweet potato’s market is about tens of billions of yuan, which means it has a promising future. Due to the difficulties of the long harvest period, high harvest requirement, and low mechanized level, the high cost and low efficiency in harvest is prominent. As such, it decreases the motivation of the farmers deeply. Also, the market still has a strong need for the stem tip harvester urgently. In order to fill the blanket in the mechanized harvest on stem tips of vegetable sweet potatoes in China, and to solve the current problems, in this research, we designed a stem tip harvester for vegetable sweet potatoes in combination with agronomy, which was composed of the reeling, cutting, conveying and collecting devices. It could finish cutting, conveying and collecting the stem tips for vegetable sweet potatoes every single row in one operation. In this paper, we introduced the harvester’s working theory based on analyzing the whole machine’s mechanical structure. To improve the integrity rate of stem tip, to lower the missing rate in cutting, to lower the stubble height and to improve the harvester’s working quality, we did a test on the harvester’s working parameters, using Box-Benhnken's central combination test method based on the single factor test. Three-level quadratic regression orthogonal experimental design was done through the forward speed, the reel speed and the reciprocating cutter line speed. The model of response surface was established to research and analysis the machine’s working quality due to different factors. Finally, the optimization of machine operation parameters was realized. The results showed that the prominent order in the stem tips’integrity rates was the reel speed > the reciprocating cutter line speed > the forward speed. The prominent order in the stem tips’missing rate was the forward speed > the reciprocating cutter line speed > the reel speed. The prominent order in the stem tip’s stubble height was the reel speed > the forward speed > the reciprocating cutter line speed. In 2019, the test was done in three times to verify the model’s correction in Baiba test base, Nanjing Research Institute for Agricultural Mechanization. The field test results showed the optimal working parameters were the forward speed 0.38 m/s, the reel speed 26 r/min, and the reciprocating cutter line speed 0.60 m/s. The integrity rate of stem tips was 97.10%, the missing rate was 12.11%, and the stubble height was 62.09 mm. The error was in the range of 5% compared to the theoretical optimization. Compared with the single manual picking efficiency of 0.001 hm²/h, the operating efficiency of this machine can reach 0.1 hm²/h, The operation effect of the machine was obviously improved compared with that of manual operation, better to meet the requirements of the vegetable sweet potatoes’stem tips machinery harvesting. The test research supplies a strong support and theoretical basis to the mechanical development of the harvester for vegetable sweet potatoes’stem tips. [ABSTRACT FROM AUTHOR]

In this study, material flow and spatial analysis methods were used to evaluate and predict the spatial–temporal pattern evolution of agricultural and rural nitrogen (N) flow in the Yangtze River Economic Belt in China from 1949 to 2050 and to analyze agricultural and rural pollution control by environmental measures. The results showed that since the founding of the People's Republic of China, the crop harvest in the Yangtze River Economic Belt has shown an overall upward trend, and the increase in the period from 1979 to 1997 was the fastest, with an average annual increase rate of 3.8%. Since the reform and opening up, N loss (storage) increased from 50.97 × 108 kgN in 1978 to 140.15 × 108 kgN in 2014, a 2.75-fold increase. In 2015, China began to implement measures to prevent and control agricultural and rural pollution, and N loss (storage) decreased yearly. In 2019, the N loss (storage) decreased by 18.22% compared with that in 2015, but it was still high. Each year, 113.44 × 108 kgN was still lost to the atmosphere, water and soil, which was 1.53 times the amount of N harvested with crops. The N loss rate was as high as 60%. Before 2014, N discharge into surface water from agricultural and rural areas in the Yangtze River Economic Belt increased annually, especially after 1978, with an average growth rate of 4.76%, leading to severe nonpoint source pollution. With the implementation of the pollution control policy, the N lost to surface water began to show a downward trend in 2015, but it was still 2.17 times higher than the environmental risk threshold in 2019. According to the prediction, under the scenarios of the business-as-usual, fertilizer reduction, engineering and rural improvement patterns, the N emissions from the system to surface water in 2050 are expected to be reduced by 25.76%, 45.5%, 30% and 30%, respectively, compared with those in 2019, but will still be higher than the environmental risk threshold. Under the integrated pattern, the N emissions to surface water are reduced to 4.32 × 108 kgN in 2050, which is lower than the environmental risk threshold and can achieve the goal of nonpoint source pollution control. A single environmental measure cannot effectively control nonpoint source pollution. It is necessary to promote an integrated pattern to achieve green and sustainable development of agriculture in the Yangtze River Economic Belt. [ABSTRACT FROM AUTHOR]

This paper reviews the current status of studies on Jatropha curcas in China. Jatropha curcas has been grown in China for more than 300 years. It is mainly distributed in the southwest from the Yunnan-Guizhou Plateau to the hot and dry Three-River Valley with hot monsoon climate and the southeast in the provinces of Fujian, Guangdong, Guangxi, Hainan and Taiwan along the coast. The regions where it occurs have annual rainfall >500 mm and average annual temperature greater than 19°C. It occurs on a wide range of soil regimes in these regions. In China the jatropha usually blossoms and bears fruits only once a year, but there are also instances of two or more flowerings per year. In some small but high yielding pilot areas, dry fruit output is reported to be 9,000–12,000 kg per ha, whereas in large plantings the output averages only about 1,800 kg per ha. In order to contribute to sustainable production of jatropha, further studies focused on different ecotypes, improvement of seed quality, plantation techniques, flowering and fruiting characteristics, and harvest and post-harvest handling of seeds are required. More research on biomedicinal potential of various parts of the plant and more information on the actual and potential markets is needed to realize the full potential of jatropha. [ABSTRACT FROM AUTHOR]

The relationship between forests and streamflows has long been an important research interest in China. The purpose of this paper is to summarize progress and lessons learned from the forest-streamflow studies over the past four decades in China. To better measure the research gaps between China and other parts of the world, a brief global review on the findings from paired watershed studies over the past 100 years was also provided. In China, forest management shifted in the later 1990s from timber harvesting to forest restoration. Forest-streamflow research was accordingly changed from assessing harvesting impacts to evaluating both harvesting and forestation effects. Over the past four decades, Chinese forest hydrology research has grown substantially. Significant progress has been made on measuring individual processes, but little solid, long-term data were available to assess the relationship between forest changes and streamflows because of an absence of standard paired watersheds. In addition, misuse of statistical analyses was often found in the literature. A unique opportunity exists in China to study the forestation effects on streamflow as several large-scale forestation programs are being implemented. Such an opportunity should include a robust paired watershed design under an integrated watershed ecosystem framework to avoid repeating the lessons already learned. Recommendations on future forest-streamflow research directions in China are provided. [ABSTRACT FROM AUTHOR]

• Spatiotemporal characteristics of trans-regional operations were first revealed. • Around 57.1 % of the harvesters completed 80.09 % of the total harvested area. • Flow and reliance of each region on harvesters were analyzed and described. • 6 provinces, 82 cities and 588 counties showed a high reliance on nonlocal harvesters. Trans-regional operation of agricultural machinery is an essential socialized service that can enhance the utilization rate of agricultural machinery and accelerate the progress of grain harvesting. In this paper, we quantitatively analyze the trans-regional operations of the harvesters using massive GNSS (Global Navigation Satellite System) data in China and reveal their spatiotemporal characteristics from the province, city and district perspectives. Trajectory data were collected from 25,763 harvesters during wheat harvesting season between May and June 2021 using the agricultural machinery operation big data system. Using the field road segmentation method for GNSS trajectory and the trans-regional operation judgment method, we calculated the quantity, driving distance, harvesting duration, and harvested area. Following this, we obtained the corresponding figures for each region, including the quantity, harvested area, harvesting duration, and distance of harvesters. To further analyze the flow and reliance on harvesters, we examined these factors at the province, city, and district scales for each respective region.. Our analysis revealed that approximately 57.1% of the harvesters were involved in trans-district operation, covering approximately 80.09 % of the total harvested area by all harvesters. Furthermore, we identified 6 provinces, 82 cities and 588 districts with a significant reliance on nonlocal harvesters. The findings provide valuable insights for the government, agricultural machinery enterprises, and agricultural machinery operators to optimize decision-making and configuration schemes to enhance the overall operational efficiency of harvesters. [ABSTRACT FROM AUTHOR]

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BACKGROUND: Global warming has led to methods of planting late‐maturing maize varieties in northeast China that have hindered the development of physiological maturity (PM) at harvest and the use of mechanical grain harvesting (MGH). Under these conditions it is difficult to balance the drying characteristics of maize varieties and to make full use of accumulated temperature resources in such a way as to reduce grain moisture content (GMC) at harvest. RESULTS: The effective accumulated temperature (AcT) and the drying rates of different varieties vary. In northeast China, with a GMC of 25%, the growth periods of a fast‐drying variety (FDV) and a slow‐drying variety (SDV) were 114–192 days and 110–188 days respectively. After PM, the FDV needed 47 days and the SDV needed 51 days to reduce the GMC to be ready for MGH. Harvested with a GMC of 20%, the growth period for the FDV was 97–175 days and for the SDV it was 90–171 days. After PM, the FDV required 64 days and the SDV needed 70 days to reduce the GMC to be ready for MGH. CONCLUSION: Matching cultivars with AcT can help farmers to choose suitable varieties. Promoting MGH may boost maize production, thus ensuring China's food security. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In view of the low level of mechanized harvesting of white radish in China and other developing countries and the current situation of "no machine can be used" due to the expensive imported machines, a self-propelled white radish combine harvester was designed based on the material, growth characteristics, and agronomic pattern of white radish. This combines harvester can realize the functions of white radish tassel gathering, deep soil loosening, clamping and conveying, tassel cutting, and collecting. In this research, the overall design of the harvester is described, and the structural and working parameters and kinematic requirements of the tassel gathering device, clamping and conveying device, tassel cutting device, and vibrating deep loosening device are determined by mechanical and kinematic analysis. Innovatively, a range of values for the tassel gathering speed ratio of 1.7–4.2 is proposed for the operation of the tassel gathering device suitable for white radish harvesting. The prototype was bench tested with the loss rate, damaged rate, and impurity rate as performance evaluation indexes. The results show that under the pitch of 240 mm between the taper angle of the tassel-raising device, a speed of 80 rpm for the tassel gathering device gathering claw belt rotation, a speed of 120 rpm for the clamping and conveying pulley rotation, a vibration frequency of 2 Hz and an amplitude of 15 mm for the vibrating deep loosening device, and a forward speed of 0.5 m/s (tassel gathering speed ratio: 1.7). The loss rate was 2.75%, the damage rate was 4.99%, and the impurity rate was 1.64%. During the operation, the innovatively designed white radish leaf gathering device can better fulfill the function of tassel gathering, and the systems worked well together, meeting the requirements of mechanized combined harvesting of white radish, but the adaptability to complex working conditions in the field needs to be further strengthened. This research can provide a reference for the design and optimization of mechanized white radish harvesting equipment. [ABSTRACT FROM AUTHOR]

Fruit maturity is a crucial index for determining the optimal harvesting period of open-field loofah. Given the plant's continuous flowering and fruiting patterns, fruits often reach maturity at different times, making precise maturity detection essential for high-quality and high-yield loofah production. Despite its importance, little research has been conducted in China on open-field young fruits and vegetables and a dearth of standards and techniques for accurate and non-destructive monitoring of loofah fruit maturity exists. This study introduces a real-time detection and maturity classification method for loofah, comprising two components: LuffaInst, a one-stage instance segmentation model, and a machine learning-based maturity classification model. LuffaInst employs a lightweight EdgeNeXt as the backbone and an enhanced pyramid attention-based feature pyramid network (PAFPN). To cater to the unique characteristics of elongated loofah fruits and the challenge of small target detection, we incorporated a novel attention module, the efficient strip attention module (ESA), which utilizes long and narrow convolutional kernels for strip pooling, a strategy more suitable for loofah fruit detection than traditional spatial pooling. Experimental results on the loofah dataset reveal that these improvements equip our LuffaInst with lower parameter weights and higher accuracy than other prevalent instance segmentation models. The mean average precision (mAP) on the loofah image dataset improved by at least 3.2% and the FPS increased by at least 10.13 f/s compared with Mask R-CNN, Mask Scoring R-CNN, YOLACT++, and SOLOv2, thereby satisfying the real-time detection requirement. Additionally, a random forest model, relying on color and texture features, was developed for three maturity classifications of loofah fruit instances (M1: fruit setting stage, M2: fruit enlargement stage, M3: fruit maturation stage). The application of a pruning strategy helped attain the random forest model with the highest accuracy (91.47% for M1, 90.13% for M2, and 92.96% for M3), culminating in an overall accuracy of 91.12%. This study offers promising results for loofah fruit maturity detection, providing technical support for the automated intelligent harvesting of loofah. [ABSTRACT FROM AUTHOR]

The Peiligang culture (ca. 9000–7000 cal. BP) represents the first Neolithic settlements in the middle Yellow River Valley, marking the beginning of millet and rice farming in the region. While previous studies have focused primarily on identifying cultivated cereals, less attention has been given to plant harvesting and processing practices or environmental conditions. To address this gap, we present new phytolith data from the Peiligang site (8000–7600 cal. BP) to make three key contributions. First, we show that the Peiligang people utilized two microhabitats: hillslopes for dryland millet cultivation and alluvial plain for wetland resources. Second, we combine our findings with other archaeological evidence to reconstruct the environmental conditions of the Peiligang site, suggesting that it was a water-rich habitat. Finally, by analyzing phytolith remains of plant processing waste in middens, we reconstruct how people harvested and processed millets and rice at the site. This study sheds light on the plant-based subsistence strategies employed by the Peiligang people and offers insights into the environmental factors that contributed to the development of early farming in the middle Yellow River Valley. [ABSTRACT FROM AUTHOR]

This study focuses on the significance of improving the land degradation of Mu Us Sandy Land to increase cultivated land area and promote ecological green development. The research objects were four kinds of mixed soils, and rhizosphere soils were collected during the crop harvesting period. The volume ratio of soft rock to sand was 0:1 (control check, CK), 1:5 (composite soil one, PS1), 1:2 (composite soil two, PS2), and 1:1 (composite soil three, PS3). The results showed that the large aggregates were primarily mechanically stable aggregates, while the small aggregates were mainly water-stable aggregates. The soft rock promoted the increase of clay and silt content in sandy soil, and the soil texture changed from sand to loam. The contents of organic matter, available phosphorus, and available potassium increased significantly under PS2 and PS3 treatments, but there was no significant difference between them. Total nitrogen had no significant difference among treatments. Actinobaciota, Proteobateria, and Chloroflexi were the dominant bacteria in rhizosphere soil, accounting for about 75% of all microorganisms. At the Genus level, the soft rock contributes to richer species composition. The diversity index, evenness index, and richness index was higher in PS1, and the available phosphorus and available potassium content promoted the increase of diversity. Therefore, when the proportion of soft rock and sand compound soil is between 1: 5 and 1: 2, it can be used as an important basis and technical parameter for Mu Us Sandy Land improvement. [ABSTRACT FROM AUTHOR]

The ridge-furrow rainfall harvesting system (RFRH) improved the water shortages, and reasonable fertilization can promote nutrient uptake and utilization of crops, leading to better yield in semi-arid regions. This holds significant practical significance for improving fertilization strategies and reducing the application of chemical fertilizers in semi-arid areas. This field study was conducted to investigate the effects of different fertilization rates on maize growth, fertilizer use efficiency, and grain yield under the ridge-furrow rainfall harvesting system during 2013-2016 in semiarid region of China. Therefore, a four-year localization field experiment was conducted with four fertilizer treatments: RN (N 0 kg hm-2, P2O5 0 kg hm-2), RL (N 150 kg hm-2, P2O5 75 kg hm-2), RM (N 300 kg hm-2, P2O5 150 kg hm-2), and RH (N 450 kg hm-2, P2O5 225 kg hm-2). The results showed that the total dry matter accumulation of maize increased with the fertilizer application rate. The nitrogen accumulation was highest under the RM treatment after harvest, average increase by 1.41% and 22.02% (P<0.05) compared to the RH and RL, respectively, whereas the phosphorus accumulation was increased with the fertilizer application rate. The nitrogen and phosphorus use efficiency both decreased gradually with the fertilization rate increased, where the maximum efficiency was observed under the RL. With the increase of fertilizer application rate, the maize grain yield initially increased and then decreased. Under linear fitting, the grain yield, biomass yield, hundred-kernel weight, and ear-grain number all showed a parabolic trend with the increase of fertilization rate. Based on comprehensive consideration, the recommended moderate fertilization rate (N 300 kg hm-2, P2O5 150 kg hm-2) is suitable for the ridge furrow rainfall harvesting system in semiarid region, and the fertilization rate can be appropriately reduced according to the rainfall. [ABSTRACT FROM AUTHOR]

E. sinensis, normally harvested in October and November, is an economic aquatic product in China. Pond culture has been widely applied for the production of E. sinensis, wherein a stable food supply for crabs is provided. In order to improve the nutritional quality of E. sinensis products, this study evaluated the effect of the local pond culture on the nutritive profiles of E. sinensis and screened out the best harvest time for the nutrient-rich crabs, thereby guiding the local crab industry to improve its aquaculture mode and harvest strategy. The results indicated that pond culture enhanced the levels of protein, amino acids, and specific organic acid derivatives, and reduced the levels of peptides and polyunsaturated fatty acids (PUFAs). Compared with E. sinensis harvested in October, peptide levels were significantly increased, whereas sugar, phenolic acid, and nucleotide levels were decreased in those harvested in November. Overall, the study revealed that the nutritive profile of the pond-reared E. sinensis was significantly modulated by a high-protein diet, thus lacking the diversity of metabolites. Additionally, October could be more appropriate for harvesting E. sinensis than November. [ABSTRACT FROM AUTHOR]

We developed an adaptive algorithm to reduce rice loss in harvesting, promote threshing and improve the quality and efficiency of small- and medium-sized rice harvesters operating in southern China's hilly and mountainous areas. Using a fuzzy PID control algorithm, the harvester adapts to the rice harvesting conditions in southern China, and monitors rice feed volume changes and instantly adjust the traveling speed to optimize feed volume levels and threshing quality. We compared and analyzed the algorithm and the traditional PID control regulation effect in the simulation experiment. The algorithm had a quicker response speed and stable accuracy. In the field trial, the average error rate was 3.4%, and the maximum error rate was 5.1%, with most data points centered around the ideal feeding rate of 3.2 kg/s. Our results showed that the algorithm's stability, accuracy, and real-time performance met the threshing loss reduction requirements of southern China's rice harvesting operations. [ABSTRACT FROM AUTHOR]

High-resolution remote-sensing imagery has proven useful for building extraction. Unfortunately, due to the high acquisition costs and infrequent availability of high-resolution imagery, low-resolution images are more practical for large-scale mapping or change tracking of buildings. However, extracting buildings from low-resolution images is a challenging task. Compared with high-resolution images, low-resolution images pose two critical challenges in terms of building segmentation: the effects of fuzzy boundary details on buildings and the lack of local textures. In this study, we propose a sparse geometric feature attention network (SGFANet) based on multi-level feature fusion to address the aforementioned issues. From the perspective of the fuzzy effect, SGFANet enhances the representative boundary features by calculating the point-wise affinity of the selected feature points in a top-down manner. From the perspective of lacking local textures, we convert the top-down propagation from local to non-local by introducing the grounding transformer harvesting the global attention of the input image. SGFANet outperforms competing baselines on remote-sensing images collected worldwide and multiple sensors at 4 and 10 m resolution, thereby, improving the IoU by at least 0.66%. Notably, our method is robust and generalizable, which makes it useful for extending the accessibility and scalability of building dynamic tracking across developing areas (e.g., the Xiong'an New Area in China) by using low-resolution images. [ABSTRACT FROM AUTHOR]

This study built mediation analysis models to test the hypothesis that a moral hazard-measured as whether harvest operators' work attitudes are serious-mediates the effects of mechanical harvest outsourcing on rice harvest losses based on a 1106-household survey in China. The major findings are as follows. First, the average rice harvest loss rate in 2016 in China was approximately 3.65%, equalling eight million tons of rice or one million hectares of farmland. Second, after addressing the potential endogeneity, we preliminarily found the mediation effect using the three-step method. The adjusted product of coefficients method from the Sobel test, distribution of the product test, and Markov Chain Monte Carlo test all indicated the significance of the mediation effect arising from work attitudes. Third, we observed the mediation effect through moral hazard for large-scale farmers, but not when farmers used combine harvesters. These results supported the presence of a moral hazard in mechanical harvest outsourcing and showed that combine harvesting could facilitate harvest loss reduction. Policymakers should consider regulating the principal – agent relationship in harvest outsourcing and encourage land transfers to form large-scale farms to promote combine harvesting. These are critical in achieving the sustainable development goal of halving food loss and waste worldwide. [ABSTRACT FROM AUTHOR]

Background: Leaves of tobacco (Nicotiana tabacum L.) are flue-cured to use as a key industrial supply in various parts of the world. The quality of tobacco leaves is dependent on chemical components and their proportions. Generally, the stem attached to tobacco leaf is detached before curing. However, the leaf stem remains green for an extended period of time (as compared to leaf) during flue-curing. Hence, it is expected to affect the quality of tobacco's final product. Results: To understand the impact of the green stem of leaf on the metabolome of flue-cured tobacco, we employed a broad targeted metabolomics approach. We selected two tobacco cultivars (Yun87 and K326) and cultivated them in five geographic locations in China. For flue-curing, leaves were harvested without a stem (L) or with an attached stem (SPL). After metabolome analysis, a total of 1027 metabolites were annotated in these samples. A variable number of metabolites were differentially accumulated between both types of leaves (depending on geographic location or cultivar) representing an influence of environment or genotype. Interestingly, only 68 metabolites were differentially accumulated between L and SPL samples irrespective of the cultivar or geographic location. These differentially accumulated metabolites belonged to major groups of primary and secondary metabolites. We have discussed the importance of identified metabolites in terms of carbon, nitrogen, and polyphenolic metabolism. Conclusion: The present research is the first comprehensive description of several metabolites in tobacco leaves related to the contribution of leaf stem. The current study opens novel prospects for investigating the potential of such metabolites in improving the quality of flue-cured tobacco. [ABSTRACT FROM AUTHOR]

The technology of the divider and lifter mechanisms of a garlic harvester using the depth limit, straw divide, and straw lift modes was studied in Lanling County, Shandong Province, China, according to the characteristics of high hardness, good uprightness and narrow row spacing of garlic planting. A test prototype of the divider and lifter mechanisms of the garlic harvester was designed and manufactured. Single-factor experiments and orthogonal regression experiments were carried out using the experimental factors of working speed, the angle of the divider, the height of the tip of the divider's tooth from the ground, the ratio of the lifter's speed to working speed and the length of the lifter's tooth. The index was the success rate of feed. The results showed that the working speed, the angle of the divider and the length of the lifter's tooth had a significant influence on the success rate of feed (p < 0.05), but the experimental factors of the height of the tip of the divider's tooth from the ground and the ratio of the lifter's speed to working speed did not have a significant influence on the success rate of feed (p > 0.05). The effects of the angle of the divider, the working speed, and the length of the divider's tooth on the success rate of feed decreased in significance. When the working speed was 0.72 km·h−1, the length of the lifter's tooth was 343.5 mm and the angle of the divider was 20°, the success rate of feed was the highest (98.18%). The research results are conducive to promoting high-quality and efficient combined harvesting of garlic in Lanling County, Shandong Province, China. [ABSTRACT FROM AUTHOR]

Reducing post-harvest loss (PHL) and waste have become important methods for alleviating food security challenges. Based on survey data from 3490 rural households in 28 provinces in China, we first estimated on-farm PHL and waste and assessed the effects of loss and waste on resources in China. We then proposed potential methods to reduce loss and waste. The results showed that the PHL levels experienced by smallholders varied for different varieties, e.g. 4.36% of maize lost in the postharvest chain, while rice and wheat losses were 5.21% and 5.67%, respectively. Meanwhile, 1.73% of the total food is wasted during consumption every day. These losses and waste caused 38.55 million tons of grain to be lost or wasted in total, which is equivalent to 7.03 million hectares of land and 373.37 billion m3 water being meaninglessly input into grain production. This also means that these losses and waste add 9.68 million tons of carbon emissions. The empirical analysis reveals that mechanical harvesting is associated with a high harvest loss, and modern storage facilities are associated with a low storage loss. To reduce these losses, modern handling practices should be improved and promoted. [ABSTRACT FROM AUTHOR]

Harvesting seasons are crucial for the physicochemical qualities of large-leaf-variety black tea. To investigate the effect of harvesting seasons on physicochemical qualities, the color and sensory characteristics of black tea produced from "Yinghong 9" (Yh) and its mutant "Huangyu" (Hy) leaves were analyzed. The results demonstrated that Hy had better chemical qualities and sensory characteristics, on average, such as a higher content of tea polyphenols, free amino acids, caffeine, galloylated catechins (GaCs) and non-galloylated catechins (NGaCs), while the hue of the tea brew (ΔE*ab and Δb*) increased, which meant that the tea brew was yellower and redder. Moreover, the data showed that the physicochemical qualities of SpHy (Hy processed in spring) were superior to those of SuHy (Hy processed in summer) and AuHy (Hy processed in autumn), and 92.6% of the total variance in PCA score plots effectively explained the separation of the physicochemical qualities of Yh and Hy processed in different harvesting seasons. In summary, Hy processed in spring was superior in its physicochemical qualities. The current results will provide scientific guidance for the production of high-quality large-leaf-variety black tea in South China. [ABSTRACT FROM AUTHOR]

The Lower Yangtze River of China has been identified as an independent center of rice domestication, but tracing the earliest evidence for rice cultivation practices has been challenging. Here we report the first evidence for rice harvesting, based on use-wear and phytolith residue analyses of 52 flaked stone tools (10000–7000 BP) from the Shangshan and Hehuashan sites. The tools reflect two harvesting methods: reaping the panicles at the top and cutting the stalk near the base. Thus, our research provides a new method for investigating prehistoric cereal cultivation, and the data lend support to the evidence of rice domestication in the early Holocene. The results also show the complexity of rice harvesting strategies several millennia before the emergence of full-fledged agriculture in the Lower Yangtze. [ABSTRACT FROM AUTHOR]